Hydriding/dehydriding behavior of MgHx-iron oxides composites

• Published in: Metals and materials international 2011-12, Vol.17 (6), p.1001-1007
• Main Authors: Kim, Kyeong-Il, Hong, Tae-Whan
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Engineering Thermodynamics; Heat and Mass Transfer; Machines; Magnetic Materials; Magnetism; Manufacturing; Materials Science; Metallic Materials; Processes; Solid Mechanics
• ISSN: 1598-9623; 2005-4149
• DOI: 10.1007/s12540-011-6019-3

Hydrogen has considerable potential as a renewable substitute for fossil fuels due to its high gravimetric energy density and environment friendliness. In particular, metal hydrides were attracted much interest given that its hydrogen capacity exceeds. One approach that can improve the kinetics is the addition of iron oxide. In this study, the hydrogen absorption/desorption properties of Mg were improved. The effect of the iron oxide concentration on the kinetics of the Mg hydrogen absorption reaction was investigated. MgH x -iron oxide composites were synthesized by hydrogen-induced mechanical alloying. The synthesized powder was characterized by XRD, SEM, and simultaneous TG/DSC analysis. The hydriding behaviors were evaluated, using an automatic Sievert’s-type PCT apparatus. The absorption and desorption kinetics of Mg catalyzed with 5 and 10 wt.% Fe 2 O 3 /Fe 3 O 4 were determined at 423, 473, 523, 573, and 623K, respectively. The results of hydrogenation properties on MgH x -Iron oxide composites were measured to be about 1.0∼4.7 wt.% under 1 MPa H 2 atmosphere.